ust_export

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are supplied, so the description carries the full burden. It does disclose two real behaviors beyond the schema: gaps in the part become 'R' rests, and the default encoding is Shift_JIS, plus the implicit fact that only one part is exported rather than the whole project. It says nothing about whether an existing .ust at ust_path is overwritten, how paths are resolved, or what permissions/state the source .ustx requires — significant gaps for a file-writing tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

A single, front-loaded sentence with zero filler, leading with the verb and the conversion being performed. It is slightly padded by a full Japanese restatement of the English text, which doubles length without adding new information for a single-language reader.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 4-parameter, no-annotation, no-output-schema file-writing tool, the definition covers the transformation semantics well but leaves out the risky parts: overwrite behavior on the destination path and required project state. An agent could call it but cannot predict whether it will clobber an existing file.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0% and the schema provides only titles, so the description must compensate. It does explain two of the four parameters ('one voice part' for part, 'Shift_JIS by default' for encoding), but ustx_path and ust_path semantics — relative vs absolute, overwrite behavior, extension handling — remain undocumented in both places.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Export one voice part of a .ustx as a classic .ust') and pins the scope to a single voice part, naming both source and target formats. An agent can immediately distinguish this from ust_import and from export_midi/export_wav, which target different formats.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The stated purpose implies a use case (converting a voice part to the UTAU format), but the definition gives no explicit when-to-use or when-not guidance and names no alternative. There is nothing about whether the project must already be open, or when to prefer this over the other export tools listed as siblings.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.